Production of metal stampings



May 15, 1934- H. T. BUCKLE 1,958,467

PRODUCTION OF METAL STAMPINGS Filed May 29. 1931 2 Sheets-Sheet l May 15, 1934- H. L. T. BUCKLE 1,958,467

Filed May 29, 1931 2 Sheets-Sheet 2 FIEL? w f m5 fo gi Honnliogggizmm Patented May 15, 1934 UNITED STATES PATENT OFFICE PRODUCTION OF METAL STAMPINGS of Pennsylvania Application `May 29, 1931, Serial No. 540,986 In Great Britain December 23, 1930 7 claims.' (c1. 11a-51) The present invention relates to improvements in the production of metal stampings and in particular to stampings which have a number of parts arranged angularly with regard to one another. As examples of such stamped bodies may be mentioned radiator shells for motor vehicles. cowls or scuttles therefor, and the like.

Hitherto it hasAbeen the practice to obtain stampings of this kind by inserting a metal sheet 10 in a press, usually in a substantially horizontal position and pressing therefrom the required stamping, by means of a vertically reciprocating die member. The metal sheet has been in area somewhat greater than the overall dimensions of the finished article. This method has the disadvantage that in most cases a considerable proportion of the blank sheet has to be cut away and is wasted. For example, in the case where a radiator shell is to be produced, the whole of the central portion of the sheet is cut away.

The present invention is directed to providing an improved method for the production of metal stampings of the kind in question whereby a. great economy of material may be effected, the area of the blank only exceeding that of the stamping to be formed by little more than is required to provide the flange which has to be engaged and held by the press during the stamping operation.

Stampings of the kind specified above are accordng to this invention obtained from blanks formed of Vmetal strips, in which are first formed in any practical manner shaped recesses or de pressions at poi'nts corresponding approximately to the angles of the final stamping. The strip is next bent or folded at these depressions, the parts on either side of the depressions being moved relatively to one another about two axes at an angle to one another, so that the parts of the blank, when folded and inserted in the press,

.40 all lie at an inclination to or across the direction of movement of the pressing tool.

The movements of the parts of the blank about two axes at an angle to one another is permitted by the shape of the depressions first placed or formed in the strip, which produce an increase in length of one edge of the blank. The lines of juncture of each depression with the surface of the blank are preferably arranged to diverge from a point near one edge of the strip and the angle oi.' divergence and thedepth of the depression are varied according to the desired relative position of the parts of the blank when folded preparatory to insertion in the press.

The invention is illustrated by way of example in the accompanying drawings in which Fig. 1 is a perspective view of a suitable blank strip for use in the production of an automobile radiator shell.

Fig. 2 is a view of the same blank after the depressions have been formed therein.

Fig. 3 is a view of the blank folded in preparation for insertion in the press.

Fig. 4 illustrates in plan view the die portion of a press for use in operating upon a blank formed in accordance with the present invention, part of the upper portion being removed.

Fig. 5 is a sectional elevation of half the press taken on the line 5-5 of Fig. 4, in the open position.

Fig` 6 is a similar view of the die closed, and 70 Fig. 7 is a plan View ofa blank of alternative form after the depressions have been formed therein.

Referring to the drawings:

The blank strip shown in Fig. l is first provided with depressions 1 and 2 at points corresponding to the angles between the top and the two sides' of the radiator shell to be formed. These depressions l and 2 stretch the metal at these points considerably on one edge and to a decreasing 90 extent towards the other edge, the work being done in a suitable die (not shown).

The depressions having been formed, the blank is now bent or foldedY at the points l and 2 to form the substantially U-shaped member shown in Fig. 3. It will readily be seen that the provision of the depressions in the blank permits the side portionsy 3, 4 to be moved relatively to the center portion 5 of the blank about two axes, one longitudinal of the strip, the other transverse, and thus to be arranged in the relative positions shown in Fig. 3, the three parts 3, 4, 5 lying in three different planes, each inclined, in this case at an angle of about 45 to the single plane containing the lower edges of all three parts.

The folded blank is now inserted in a press such as is shown in Figs. 4 to 6.

The stationary supporting surface upon which the folded blank is laid is in plan substantially the same in shape as is the blank, as will be seen from Fig. 4.

The blank, as will be seen in Fig. 5, rests upon the surfaces 8 which slope towards the interior of the press. The blank is indicated by l0. Round the stationary portion of the die between the sloping surfaces 8 there runs a recessed portion 6. The upper or movable portion of the die is of the known type wherein a clamping portion 9 ilrst descends and holds the edges of the blank 10 rmly against the surfaces 8 Vwhereupon the 110 plunger member 'IA descends, meeting the blank 10 in a direction at an angle to its plane and forcing the material of the blank into the recessed portion 6 of the stationary die. 'I'he anges 11 of the blank which are held between the clamping portions 9 of the press and the supporting surface 8 are subsequently removed after the blank is taken from the press. It will be seen that the wastage is comparatively small.

While the invention has been described above as applied to the production of an automobile radiator' shell, it will be understood that it is equally applicable to the production of numerous other articles having a number of parts arranged at angles to one another and the invention is not limited as to the number of bends or angles in the folded blank. By suitably determining the shape and dimensions of the forms or depressions rst formed in the blank, it is possible to prepare blanks which are adapted to be operated upon by dies or tools of any particular shape.

While in the case described above the lower edges of all the parts of the blank when folded lie in one plane, it is to be understood that this is not essential to the carrying out of my invention.

The present invention is not confined to operations starting with a straight strip blank. Thus, for example, the blank may be in the form illustrated in Fig. 7, and the depressions formed with their width decreasing from the inside angles of the blank towards the out-side angles, which again permit of the blank being bent into the shape of Fig. 3. Equally in some cases strip blank may be employed having one or more curved sides.

l. The method of making a metal stamping which comprises forming a depression in the blank, in folding the blank about an axis in the depression and in bending the blank across said axis while holding its margins.

K, 2. The method of making a metal stamping which comprises forming an elongated depression in the blank in folding the blank about an axis along the depression and in bending the blank across said axis while holding its margins.

3. The method of making a metal stamping which comprises forming a tapered depression in the blank, in folding the blank substantially about the central axis along the depression whereby the degree of taper substantially determines the angular relation of sections of the blank at opposite sides of the fold, and in bending the blank across the fold while holding its margins.

4. The method of making a metal stamping which comprises forming a tapered depression inwardly converging from one edge of the blank, in folding the blank about an axis along said depression and in bending the blank across the fold while holding its margins.

5. The method of making a metal stamping which comprises forming a depression that extends inwardly from one edge of the blank to a position in the plane of the blank short of the f blank across the fold while holding its margins.

7. The method of making radiator shells from flat strip stock which comprises indenting the strip, bending the strip about an axis of the indentations and forming said strip to a smooth surface transversely of the indentations while holding its margins.

HORACE LEOPOLD TUCKER BUCKLE. 

